1. Field of the Invention
The present invention relates to a terminal directly mounted on a printed circuit board, a construction to directly mount a terminal to a printed circuit board, a printed circuit board to which a terminal is directly mounted, and an electric junction box that houses a printed circuit board or a printed circuit board on which a terminal is directly mounted. More particularly, the present invention relates to a terminal that is inserted in a through hole in a printed circuit board and soldered to the through-hole, and the terminal is positioned and fixed to the printed circuit board in a simple and secure manner without damage, thus enhancing alignment accuracy of the terminal.
2. Description of Related Art
Conventionally, terminals directly mounted on a printed circuit board include a press-fit terminal, which is pressed into a through-hole in a board and press-contacted on a conductor coated on an inner circumferential surface of the through-hole for connection; and a terminal that is inserted into a through-hole in a printed circuit board and soldered for connection with a circuit. The prior art also includes a terminal that includes an end portion split into a plurality of board connecting portions that are inserted into through-holes in a printed circuit board. The board connecting portions are inserted into respective through holes provided in the printed circuit board and soldered for electric connection.
For example, Japanese Patent Laid-open Publication No. 2005-135698 discloses a press-fit terminal 1, as shown in FIGS. 5A and 5B. The press-fit terminal 1 includes an end portion split into two board connecting portions 2a and 2b, which are press-fit into printed circuit board 3 through holes 4a and 4b, respectively. The through holes 4a, 4b each include an inner wall plated with a conductor. Further, Japanese Patent Laid-open Publication No. 2003-272737 discloses a terminal 5 for high current, as shown in FIGS. 6A and 6B. The terminal 5 includes an end portion split into two board connecting portions 6a and 6b, which are inserted into printed circuit board 7 through holes 8a and 8b, respectively. The through holes 8a, 8b each include an inner wall plated with a conductor. Spaces between the through holes 8a, 8b and the board connecting portions 6a, 6b are filled with solder 9 for connection with a circuit on the printed circuit board 7.
However, the conductor on the inner wall of the through holes 4a, 4b is easily scratched when the press-fit terminal 1 is pressed in, thus causing a conduction failure in both board connecting portions 2a and 2b. Further, after insertion into the through holes 8a, 8b, the terminal 5 is pressed from above and held by a jig until soldered, thus easily causing terminal misalignment or deformation and requiring alignment adjustment. These problems associated with the prior art are not limited to high current terminals, but also occur in press-fit terminals and solder-mounted terminals that include a terminal connecting portion that is not split.